crypt: [18] The Greek adjective kruptós meant ‘hidden’. From it was derived kruptikós, which passed into English via late Latin crypticus as cryptic [17]. The feminine form of the original Greek adjective, krúptē, was used as a noun meaning literally ‘hidden place’, thus ‘underground chamber, vault’; English acquired it via Latin crypta. From the same ultimate source comes apocrypha [14], literally ‘books of hidden – that is, unknown – authorship’. => apocrypha[crypt etymology, crypt origin, 英语词源]